Askin server name on 2 mobile devices

[Emsalem]

I´ve installed the mobile version in several mobile phones ( android) wtih no issues using the QR code, but in 2 devices it´s asking a server name ( see attached screen), and no idea what server is this 

Any ideas ?

One of the mobiles never had the instalation before, but the other had this same error before while in the trial version, tried to pud the official version and same error